Frappe.route_options

frappe.listview_settings[‘Task’] = {
onload: function(listview) {
listview.page.add_inner_button(“More filters”, function() {
frappe.call({
method: ‘frappe.client.get_list’,
args: {
doctype: ‘Project’,
fields: [‘name’]
},
callback: function(r) {

                let project_names = r.message.map(project => project.name);
                console.log(project_names);
                
                let d = new frappe.ui.Dialog({
                    title: 'Enter details',
                    fields: [
                        {
                            label: 'Sub Projects',
                            fieldname: 'sub_project',
                            fieldtype: 'MultiSelectPills', 
                            options: project_names 
                        }
                    ],
                    size: 'small',
                    primary_action_label: 'Submit',
                    primary_action(values) {
                        console.log(values.sub_project);
                        
                        d.hide();

                        
                        frappe.route_options = {
                            "sub_project": ["in", values.sub_project]
                        };
                        frappe.listview_settings['Task'].after_submit(listview, values.sub_project);
                    }
                });
                
                d.show();
            }
        });
    });
},

after_submit: function(listview, sub_project){
    console.log("hhaha",sub_project); 
    frappe.route_options = {
        "sub_project": ["in", sub_project]
    };
    listview.refresh();
}

};

can any one hellp me why does route_options wont work

Reference: List View filter - #2 by NCP

hi sir i just want to know if its possible to add in filter list the Table Multiselect?

Not sure, but try it yourself.